Add 881 in c language

c/881-boats-to-save-people.c

@@ -0,0 +1,32 @@
+/*
+
+Space: O(n) (because of quicksort)
+Time: O(nlog(n)) (because of quicksort)
+*/
+
+int cmp(const void* a, const void* b) { // Function of comparison for quicksort
+ return *(int*)a - *(int*)b;
+}
+
+int numRescueBoats(int* people, int peopleSize, int limit){
+ int cpt=0;
+ qsort(people, peopleSize, sizeof(int), cmp);
+ int i=0;
+ int j=peopleSize-1;
+ while (people[i]+people[j] > limit && j>0)
+ j--;
+ cpt += peopleSize-j-1;
+ while (i<j) {
+ if (people[i]+people[j]<=limit){ // Boat for 2 people
+ i++;
+ j--;
+ cpt++;
+ } else { // Boat for 1 person
+ cpt++;
+ j--;
+ }
+ }
+ if (i==j) // Boat for 1 person
+ cpt++;
+ return cpt;
+}